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88 DESIGN007 MAGAZINE I SEPTEMBER 2020 sing before going any further with your design. Therein, you will find paragraphs of recom- mendations on how to mitigate outgassing, as well as references to other IPC and non-IPC guidelines and requirements for that specific issue. Proposed Revisions to IPC-2231 While it is still in development and may change (more on that later, and how you can help shape it), the current proposed draft of IPC-2231A builds on its predecessor by propos- ing greater depth to many existing sections, streamlining others, and even adding entirely new content to better address design chal- lenges faced by board engineers. The printed board assembly design process section is proposed to be enhanced to bet- ter elaborate on the steps necessary to iterate through the design process: concept design and analysis, detailed design, first build, prod- uct validation, manufacturing validation, and support. Specifically, the detailed design step is proposed to be reinforced by additional detail concerning design documentation. An entirely new step in the process—manufacturing vali- dation—is also being considered for addition to IPC-2231A. The largest proposed addition to the IPC-2231A is a brand-new section on design impacts on fabrication processes and includes discussion, recommendation, and references to help the user design for critical fabrication processes—such as the application of surface finishes or preparing a board for laser drilling. Standards Development But these proposed changes are exactly that—proposals. The servants of industry who have made these proposals comprise the IPC 1-14 DFX Subcommittee responsible for the development of IPC-2231A. As the IPC staff liaison to the 1-14 Subcommittee, I had the pleasure of attending every bi-weekly develop- ment meeting for the past year and listening in on how some of the leading experts in the field conduct their meetings and build their document. This group has three co-chairs from around industry: Karen McConnell of Northrop Grumman Corporation, Steve Golemme of Google Inc., and Dock Brown of DfR Solutions. Along with a small group of dedicated volun- teers, these three individuals have coordinated the recent efforts to revise IPC-2231. For those who might be unaware of how IPC standards are developed, the most common strategy is to deploy A-Teams who handle chapters, sections, or even single figures for a larger standard or guideline. The 1-14 Subcommittee employed these A-Teams to great effect by selecting indi- viduals with the most expertise of the various DFX topics to work on those sections. While this might seem so obvious as to be a trivial point, I think that it is worth exploring as a call to action. Even if you think that your expertise is only applicable to 5% of a given standard—not even necessarily an IPC stan- dard—then that expertise is welcome. In the case of IPC-2231, there are many discrete sub- sections that deal with related, but not neces- sarily linked, topics. For example, in contrast to the thermal pad outgassing issue noted above, there is a section detailing design guidelines for system enclosures only five pages later. If you know very little about thermal pad out- gassing but quite a bit about best practices for designing system enclosures, then your input on only that small fraction is critical for the good of the whole document. Of course, there are individuals who know "a whole lot about a whole lot," and they are more than welcome to sprinkle their knowledge over the entire document. This was the case for many of the dedicated industry veterans who donated their time and talent to the production of IPC-2231A. IPC-2231A is currently in working draft and is being reviewed by the committee until Septem- ber 18, 2020, at which point it may be tweaked per any feedback received after review. The final draft of the document will then be deliv- ered to the industry for a mandatory 30-day review period. The beauty of transparent and open document development is that during this industry review period, any individual can ren- der comments on the document, even if they are not members of the committee or have not previously worked on the document.

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